wifi: ath10k: Remove redundant argument offset

This argument of ath10k_htt_rx_h_frag_pn_check() is always set to 0 so
drop this.

Signed-off-by: Zhi-Jun You <hujy652@gmail.com>
Signed-off-by: Kalle Valo <quic_kvalo@quicinc.com>
Link: https://lore.kernel.org/r/20221110164025.14418-1-hujy652@gmail.com